Do you need a break in order to keep working? No, you don’t:

In a paper published this week in Psychological Science, the researchers challenge a long-held theory that willpower – defined as the ability to resist temptation and stay focused on a demanding task –is a limited resource. Scientists have argued that when willpower is drained, the only way to restore it is by recharging our bodies with rest, food or some other physical distraction that takes you away from whatever is burning you out.

Not so, says the Stanford team. Instead, they’ve found that a person’s mindset and personal beliefs about willpower determine how long and how well they’ll be able to work on a tough mental exercise.

“If you think of willpower as something that’s biologically limited, you’re more likely to be tired when you perform a difficult task,” said Veronika Job, the paper’s lead author. “But if you think of willpower as something that is not easily depleted, you can go on and on.”